β-Lactam antibiotics (e.g. penicillins and cephalosporins) are an important class of antibacterial agents widely used in clinical therapies and as health promoting agents in animal feedstuffs. The clinical function of β-lactam antibiotics relies on their inhibitory effect on the activity of penicillin-binding proteins which are responsible for synthesizing bacterial cell wall. However, the clinical importance of β-lactam antibiotics has been challenged by the emergence of β-lactamases which are capable of inactivating β-lactam antibiotics by hydrolyzing the β-lactam ring to carboxylic acid. To respond to this clinical problem, the pharmaceutical industry has produced a wide range of β-lactam antibiotics (which have stronger resistance toward the hydrolyzing action of β-lactamases) and new β-lactamase inhibitors (which can irreversibly block the enzyme's active site via covalent modification). In order to search for a potent antibiotic from a large pool of drug candidates rapidly, a convenient tool that can screen bacteria for β-lactamases against a panel of various antibiotics is desirable. Moreover, a sensing tool that can detect β-lactamase inhibitors and β-lactam antibiotics can also be useful. Such a tool can be used in the discovery of β-lactam antibiotics and new β-lactamase inhibitors, and utilized in routine measurement of antibiotic residues in liquid and food samples (e.g. milk).